I remember the fun I had working at a gas station growing up and the people who would come in and treat me as if I didn't have a brain. Apparently, to many of the customers, it wasn't logical that a college kid with a high IQ could possibly want to work behind the counter of a gas station on weekends to pay for college.
I learned a lot about Human Resources and motivation in my time at the gas station. It was funny to see the interactions between people who were getting their car worked on and the mechanics and service manager. It was also rewarding to be able to manage kids my age in terms of writing their schedule and training them.
Next time you are in a gas station, convenience store, or other "service" establishment, engage the person working there in a conversation; you'd be pleasantly surprised with what you may find out about them in the discussion.
Likewise, if you work in a position at one of these establishments, look beyond the stereotypes of the role and find ways to make the work interesting, as well as opportunities to engage your customers in friendly dialogue (in fact, many of the people I talked to in my time at the gas station are clients or friends today, some 20 years later!)